```ts
// Button.stories.ts

import { Meta } from '@storybook/angular/types-6-0';

import Button from './button.component';

export default {
  title: 'Button',
  component: Button,
  argTypes: {
    backgroundColor: { control: 'color' },
  },
  args: {
    // Now all Button stories will be primary.
    primary: true,
  },
} as Meta;
```
